IN-E-HyFlex-V4_10
Rotronic AG
Bassersdorf, Switzerland
Document code
Unit
Instruction Manual
Document Type
HygroFlex transmitter version 4: instruction
manual
Document title
Page
48
of 61
© 2006; Rotronic AG IN-E-HyFlex-V2_10.doc
c) The temperature of the air stream should be practically constant.
If you cannot meet the above requirements, you should not attempt to calibrate temperature.
13.2 Humidity calibration
ROTRONIC provides easy-to-use, certified humidity standards for customers who do not have
access to a humidity generator. To use these standards, you will need a calibration device that
is suitable for your probe.
Calibration device
The calibration device is a small airtight container that fits on the probe and seals around the
humidity sensor. During calibration, a known reference humidity is produced inside the
calibration device by means of a humidity standard (usually an aqueous salt solution).
The following calibration devices are available from ROTRONIC:
ER-15: for 15mm diameter probes
ER-05: for 5 mm diameter probes
EM-15 for probe type IE
ERV-15 for probe type IW
Certified humidity standards
The ROTRONIC certified standards are available in boxes of 5 glass ampoules of the same
value, which can be stored indefinitely. Standards in the range of 5 to 95 %RH are non-
saturated aqueous salt solutions that are precisely titrated at our factory for the right
concentration. The 0 %RH humidity standard is made of small granules of a highly porous
ceramic that have been dried at a high temperature. A Material Safety Data Sheet is available
for each standard. Since most standards are a salt solution, parts which have come in contact
with the liquid should be cleaned after each use.
Each box of standards comes with a certificate that provides statistical information on the
manufacturing batch of the standard. Information on the effect of temperature on each
standard is provided on the cover of each box of standard. When calibrating either with the
HygroFlex or with the HW4 software, the effect of temperature on the standards is
compensated by the software and no further correction is required. The value of the standards
is not affected by altitude.
Instructions for using the standards
•
Install the calibration device on the probe so that the receptacle (or solution holder) is
under the probe. Check for a tight fit and remove the receptacle from the calibration device.
•
Place one fiber disc (each box of standards includes 5 discs) in the receptacle of the
calibration device. The purpose of this disc is to prevent accidental spilling of the solution
inside the calibration device or on the humidity sensor.
